A110-6 TRAPEZOID QUADRATURE VCO

The module is based on an idea by Donald Tillman from 2003 but has been revised for the use of modern electronic circuits (no OTAs/CA3280). Because of it's unique trapezoid core it's totally different compared to other VCOs. But the trapezoid core is not the only specialty: it is also a quadrature VCO and features linear thru zero frequency modulation.